When an exasperated mother left her fussy 4-year-old alone in the car for a few minutes while she ran an errand, she never imagined that split-second decision would lead to criminal charges.

“I don’t think I put my child in danger,” Kim Brooks told “20/20.” “[But] some people certainly think I’ve made a mistake. Some people, very strongly, feel that children should never be out of your sight… and that I took a risk I shouldn’t have.”

It was March 2011. Brooks was running late to catch a flight with her two young children, her then-4-year-old son and then-18-month-old daughter, when she realized her son’s headphones that he used to watch movies and play games with on her iPad were broken and she didn’t have a spare. She decided to run to the store to get new ones, leaving the baby in her mother’s care and taking her son with her.

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Kim Brooks sat down with ABC News' "20/20" to talk about her ordeal.

When she got to the store parking lot, Brooks said her son was playing a game on the iPad and was putting up a fight about coming in with her. Instead of risking a temper tantrum in public, Brooks decided to leave him behind in the car -- something she said she had never done before.

“It was really a split-second decision,” Brooks said. “I didn’t sit there and mull it over for very long because I was in a hurry. At that moment, it felt safe. It was a pretty quick decision.”

“It was a cool day. It was probably under 50 degrees, overcast day, and it was a safe neighborhood,” she continued. “So at that moment, I just thought, I’m not putting him in harm’s way by... letting him wait in the car while I get this one item.”

So Brooks parked as close to the store as possible, cracked the windows, locked the car doors, which activated the car’s alarm system, and ran in. When she returned a few minutes later, she said her son was still there happily playing his game. So she drove home, picked up the baby and the luggage, headed to the airport and made their flight.

But what Brooks didn’t know at the time was that someone in the store parking lot had been watching her. Using his cell phone camera, an anonymous person allegedly videotaped her leaving her son alone in the car, and then coming back minutes later and driving away. Then, this person turned the video into police, who traced the license plate on the car back to Brooks.

Brooks was charged with contributing to the delinquency of a minor, a misdemeanor that carries a maximum sentence of one year in jail and a fine.

“When that happens, you’re not just being called a bad mother, but you’re being charged, basically, with being a bad mother,” she said. “It’s very humiliating and very embarrassing.”

According to the National Highway Traffic Safety Administration, 605 children died in hot cars from 1998 to 2013.

Even though Brooks left her son alone in the car only for a few minutes on a cool day in March, not for hours on a hot summer day, there are some who believe what she did should be illegal.

Sue Auriemma is the vice president of KidsandCars.org, an organization that raises awareness about public safety issues surrounding children and vehicles. She believes that there is never a situation where it's safe to leave a child alone in a car.

“A car is not a babysitter,” Auriemma said. “People have said to me, ‘for just a short period of time. It’s just a few minutes. It’s OK.’ To me, that’s akin to saying you need to go far away from your home before you get into a car accident so within a mile of your house you don’t need your seat belt. It can happen in an instant.”

A car can pose “many other dangers,” Auriemma said, not just heatstroke on a hot day, but also seat belt strangulation and injury with automatic seat adjustment settings, which move seats up and down or backwards and can crush or trap a child.

“The child is unsupervised and it doesn’t take a long time for something bad to happen to a child,” she said. “Several states have introduced Good Samaritan laws... that would allow someone to break a window if they see a child that they believe is in danger without facing legal implications.”

But Lenore Skenazy, the founder of Free Range Kids, which aims to teach parents not to be overprotective, believes that the “baby in hot car” debate is too narrow-minded, and while parents should never leave children alone for hours, a few minutes in the car is “not a dangerous situation.”

“There’s no reason to criminalize the parents who let their kids wait in the car for a short while, while getting the pizza, or picking up some stamps,” Skenazy said. “[Heatstroke in a car] certainly is a horrific way to die. So is a car crash, so is falling down the stairs. For some reason, we’re just focusing on this very rare, awful way to die.”

In looking at child auto deaths overall, Skenazy said children dying in parked cars is actually rare, and as many as 1,200 kids under age 14 die in car accidents while on the road each year. Skenazy believes that “society has become hysterical” about the kids in cars topic because it “sounds crazy."

“It is completely unrealistic to expect that every second of every day should not only be perfect, but should be optimal in the eyes of every onlooker,” Skenazy said. “The idea that if you let your kids wait in the car and something terrible happens, it’s because you were a bad parent. But if you take your kids out of the car, and you bring them in to pay your gas bill, and there’s a stick-up and the children are all murdered, that’s not a bad parent. Either way, we’re talking about something very rare and very random happening.”

As for Brooks, instead of risking a trial in juvenile court, where the court could rule to have her children taken away, she attended parenting education courses and complete 100 hours of community service. The prosecutor decided not to press charges.

In the aftermath of the lengthy legal battles, Brooks said her son suffered from separation anxiety.

“Not just typical separation anxiety,” she said. “He would say things like, ‘the police are going to come, stay beside me,’ or that I would get in trouble.”

To this day, Brooks said she has not seen the alleged video showing her leaving her son alone in the car, nor does she want to, but she wishes the person who videotaped her had confronted her directly instead of sneaking around and going to the police.

“I think of a good Samaritan as someone who helps out, who helps a stranger, who behaves neighborly towards someone, even if they don’t know that person,” Brooks said. “I don’t think what they did really helped me or my child.”

As for deciding whether to leave a child alone in the car, Brooks said it depends on the circumstances, and if it’s not against the law, it should be up to the parent.

“Parents need to have some right to sort of make these choices about what risk is reasonable to take,” she said. “I think I’m sort of like most parents, and I think that most parents are doing the best they can to protect their children.”

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